Lanthanide oxides such as europium oxide (Eu2O3) and gadolinium oxide (Gd2O3) are known for their light emitting and high-K dielectric properties, respectively [76, 58, 77]. The Eu3+-doped Gd2O3, in microcrystalline form, has been employed in video displays and tri-color fluorescent lamps as a red phosphor [78]. Recently, nanocrystalline form of Eu3+-doped sesquioxides has gained research interest due to their potential use in luminescent biological tags, efficient light emitting devices, and high-resolution displays. Gd2O3 has received research attention because of its high-κ dielectric properties. Gd2O3 has been proposed as silicon dioxide replacement for gate oxide in ultra-small complementary metal-oxide-semiconductor (CMOS) devices [77]. Most applications of luminescent and dielectric materials require their implementation in thin-film form. The Eu2O3 and Gd2O3 nanocrystals, made via colloidal techniques, need to be assembled into thin-film form to study their optical and dielectric properties.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.